Typing-extensions

- Add `typing_extensions.Any` a backport of python 3.11's Any class which is
subclassable at runtime. (backport from python/cpython31841, by Shantanu
and Jelle Zijlstra). Patch by James Hilton-Balfe (Gobot1234).
- Add initial support for TypeVarLike `default` parameter, PEP 696.
Patch by Marc Mueller (cdce8p).
- Runtime support for PEP 698, adding `typing_extensions.override`. Patch by
Jelle Zijlstra.
- Add the `infer_variance` parameter to `TypeVar`, as specified in PEP 695.
Patch by Jelle Zijlstra.

- Add `typing_extensions.NamedTuple`, allowing for generic `NamedTuple`s on
Python <3.11 (backport from python/cpython92027, by Serhiy Storchaka). Patch
by Alex Waygood (AlexWaygood).
- Adjust `typing_extensions.TypedDict` to allow for generic `TypedDict`s on
Python <3.11 (backport from python/cpython27663, by Samodya Abey). Patch by
Alex Waygood (AlexWaygood).

- Re-export `typing.Unpack` and `typing.TypeVarTuple` on Python 3.11.
- Add `ParamSpecArgs` and `ParamSpecKwargs` to `__all__`.
- Improve "accepts only single type" error messages.
- Improve the distributed package. Patch by Marc Mueller (cdce8p).
- Update `typing_extensions.dataclass_transform` to rename the
`field_descriptors` parameter to `field_specifiers` and accept
arbitrary keyword arguments.
- Add `typing_extensions.get_overloads` and
`typing_extensions.clear_overloads`, and add registry support to
`typing_extensions.overload`. Backport from python/cpython89263.
- Add `typing_extensions.assert_type`. Backport from bpo-46480.
- Drop support for Python 3.6. Original patch by Adam Turner (AA-Turner).

- Fix importing `typing_extensions` on Python 3.7.0 and 3.7.1. Original
patch by Nikita Sobolev (sobolevn).

- Runtime support for PEP 646, adding `typing_extensions.TypeVarTuple`
and `typing_extensions.Unpack`.
- Add interaction of `Required` and `NotRequired` with `__required_keys__`,
`__optional_keys__` and `get_type_hints()`. Patch by David Cabot (d-k-bo).
- Runtime support for PEP 675 and `typing_extensions.LiteralString`.
- Add `Never` and `assert_never`. Backport from bpo-46475.
- `ParamSpec` args and kwargs are now equal to themselves. Backport from
bpo-46676. Patch by Gregory Beauregard (GBeauregard).
- Add `reveal_type`. Backport from bpo-46414.
- Runtime support for PEP 681 and `typing_extensions.dataclass_transform`.
- `Annotated` can now wrap `ClassVar` and `Final`. Backport from
bpo-46491. Patch by Gregory Beauregard (GBeauregard).
- Add missed `Required` and `NotRequired` to `__all__`. Patch by
Yuri Karabas (uriyyo).
- The `final` decorator now sets the `__final__` attribute on the
decorated object to allow runtime introspection. Backport from
bpo-46342.
- Add `is_typeddict`. Patch by Chris Moradi (chrismoradi) and James
Hilton-Balfe (Gobot1234).

- Fix broken sdist in release 4.0.0. Patch by Adam Turner (AA-Turner).
- Fix equality comparison for `Required` and `NotRequired`. Patch by
Jelle Zijlstra (jellezijlstra).
- Fix usage of `Self` as a type argument. Patch by Chris Wesseling
(CharString) and James Hilton-Balfe (Gobot1234).